Blindstitch seaming mechanism.



W. MORRISON. BLINDSTITGH SEAMING MECHANISM.

. APPLICATION FILED DOT. 21, 1911. 1,071,452. Patented Aug. 26, 1913.

- a SHEETS-SHEET 1.

W. MORRISON. BLINDSTITOH SEAMING MECHANISM.

APPLICATION TILED 001221, 1911.

Patented Aug. 26, 1913.

3 SHEBTS-SHEET 2.

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Masa- COLUMBIA PLANOORAPH CO WASHINCIT ON, D. c.

W. MORRISON. BLINDSTITGH SEAMING MECHANISM, APPLICATION FILED 001. 21 1911.

1,071,452. Patented Aug; 26, 1913.

3 SHEETS-SHEET 3.

WILLIAM MORRISON, OF PHILADELPHIA, PENNSYLVANIA.

BLINDSTITCI-I SEAMING MECHANISM.

Specification of Letters Patent.

Application filed October 21, 1911.

Patented Aug. 26,1913. Serial No. 655,886.

To all whom 2'15 may concern:

Be it known that I, WILLIAM MORRISON, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented Improvements in Blindstitch seaming Mechanism, of which the following is a specification.

My invention consist-s of a blind stitch forming mechanism, which is particularly adapted for seaming leather for use in gas bellows, or the like, where the seams must be gas tight.

The chief object of my invention is to construct a machine that will quickly make a blind stitch seam which will be more accurate than any made heretofore and which will be gas tight.

Another object is that the'machine thus constructed may be easily operated, durable,

and can be manufactured at a small cost.

:seam is constructed; Fig. 6, is a sectional perspective view showing the finished seam; and Fig. 7, is a View showing a modified form of clamp.

Referring to the drawings, 1 is the bed of a sewing machine; 2 isv the needle; 3 is the feed plate; and 4 is the work plate. These sewing elements may be of any construction and are employed to cotiperate with my invention but I prefer to use a side pointed needle having a fiat cross section. A presser foot 3 is provided with an eyelet plate 2 through which the reciprocable needle 2 passes during the sewing operation. An adjustment carriage 5 is placed adjacent the work plate 4 and comprises a substantially fixed base 6 having a slide 7 thereon.

The base 6 has a projection 8. through which passes a threaded spindle 9. A nut 10 is fixed to the slide 7 and receives the threaded portion of the spindle 9. The base 6 is clamped to the bed 1 by a set screw 6 and may be turned and clamped at any angle. A double-armed standard 11 is formed integral with the slide 7 and has roller bearings journaled, one at each end, as clearly shown in Figs. 2 and 3.

A feed carriage 13, in the present instance in the form of a grooved bar, is slidably mounted so as to bear on the roller bearing 12 and between the flanged portions 14 of the standard 11. Pins 15 are screwed through the flanged portions 14 and enter the grooves of the carriage 18, thus serving as retainers to keep said latter carriage always in contact with the roller bearings 12. The carriage 13 is provided with journal plates 16 having bearing slots 17.

A clamping or material supporting plate 18 is provided with trunnions 19 which are adapted to rest within the bearing slots 17. The clamping plate 18 has a groove 20 formed therein, and a correspondingly projecting face 21. A wedge 21 substantially V- shaped in cross-section forms a clamp jaw and is provided with two threaded projections 22 which pass through bores 23 in the clamp plate and also through bores 24 in an upper pressure bar 25. The pressure bar 25 is provided with a beveled jaw or pressure plate 25" which is designed to clamp the upper run of the material to be seamed against the bevel face 21'. Adjustment nuts 26 are mounted on the free ends of the threaded projections 22 and form the means whereby the wedge, clamping Plate 18 and upper pressure bar 25 are drawn together, to tightly draw the leather around the end 18 of the said clamping plate 18.

\Vhen the ends of a strip of bellows leather are to be secured together by blind stitching to form a gas bellows the operat-ionwis as follows: The two ends 27 and 28 of the said bellows leather, after being lapped and pasted, are drawn over the clamping plate 18. The threaded projections 22 of the wedge 21 are then passed through the bores 23 of the said clamping plate and the bar 25 placed on the clamping plate 18 so that the projections 22 will pass through the bores 24. The nuts 26 are then screwed on the free ends of the projections 22 to tightly clamp the two ends of the bellows leather. The clamping plate is then mounted on the carriage 13 so that the trunnions 19 rest within the bearing slots 17 and the clamping member 18, supporting the bellows leather, rests on the work-table 4. The spindle 9 is then turned to move the needle will perforate the thickness of the end 2'? only from its outside surface, and.

not through the entire thickness, as clearly shown in Figs. 5 and 6. The end of the plate 18 is, therefore, made substantially parallel at all points with the plane of the path of the needle and as the clamping plate 18, together with its cooperating members 21 and 25 holds the end 27 tightly against the end 18 the needle will pass through the center of the thickness of the said end 27; preventing the inner surface of the end 27 of the bellows leather from becoming perforated.

In the operation, after the leather has been mounted between the clamping members and adjusted in the proper position be neath the needle by the operation of the spindle 9, the same is fed to receive the stitching by the usual feed plate 18, as the carriage 13, having very little friction, will move with the clamping members in response to the friction exerted by the feed plate 3. In order that the finished bellows leather may be quickly and easily removed from the clamping members, the plate 18 is provided with a cam face which, when.

the same is turnedin the position of the dot and dash lines, Fig. 2, will raise the trunnions 19 out of the bearing slot 17 to allow the said clamping means to be bodily removed from the carriage. In other words, the operator may remove the entire clamping members from the bearing slots 17 by simply swinging the clamp plate 18 up as shown in dot and dash lines Fig. 2. To re move the seamed leather: the nuts 26 are removed from the threaded projections 22 to allow the separation of the clamping members; the leather may then be slid from the clamping plate 18.

In Fig. 7, I have shown a modified form where the clamping members are all substantially flat.

By having the adjustment carriage operated by the spindle 9 there is no possibility of a lateral movement thereof due to the action of the needle tending to slide the leather out of itspath. Likewise the needle cannot spring orglance off the leather because the eyelet of the presser foot formsa guide for the needle directly above the sewing point. Thus with the mechanism as illustrated an extremely thin strip ofleather or other material can be blind seamed; the

25 and also to the distance between the said wedge 21 and the portion of the adjustment nuts which contact with the member 25. For example, if it is desired to place more tension on the material to stretch the latter more tightly against the end 18 of the clamping plate, the adjustment nuts are turned ontheir respective threaded projections so that the wedge 21 will move toward the adjustment nuts. On the other hand, if it is desired to reduce the amount of tension on the material the adjustment nuts may be backed-01f their respective threaded projections which will release the pressure of the wedge 21 and jaw 25 on the said material. Thus it-is obvious that the threaded nuts and projections form adjusting means for varying the degree of tension and pressure of the strip material around and against the said edge 18 The action of my invention is such that while the presser foot and feed plate tend to prevent the material from vibrating vertically during the entrance and withdrawal of the needle, the end 18 of the pivoted clamp plate and the eyelet 2 of the presser foot prevent any lateral movement. Thus, as above mentioned,the needle can pass through the crease or folded port-ion of a very thin piece of material without perforating the inner surface thereof. The invention is therefore especially valuable as this seaming can be done with the usual speed and number of stitches per inch of any sewing machine onthe market.

While I have describedmy machine as be ing particularly valuable in the seaming of leathery'it will be understood that the same is etlicient in seaming other materials.

I claim:

1. The combination with a stitching mechanism including a needle of a supporting plate having a fold defining edge; means for securing material to the supporting plate; adjusting means operable upon the said securing means for varying the degree of tension of the said material only transversely to and againstone edge-of the said supporting plate, and means for guiding'the plate with said edge at a predetermined distance from the needle path.

2. The combination, with a stitching mechanism including a needle, of a material supporter-having a fold defining edge; means for securing material to the said supporter;

adjusting means passing through said material supporter and operable to move the said securing means for varying the degree of tension of the said material against one edge of the material supporter and means for guiding the supporter with said .edge at a predetermined distance from the needle path.

3. The combination withastitching mechanism of a material supporting plate having a straight edge; means for securing material to the supporting plate; and adjusting means operable upon the said securing means for varying the degree of tension of the said material against the said edge of the material supporting plate.

4. The combination, with a stitching mechanism, of a material supporter having a fold defining edge; means including two members for contacting with the said material and having the material supporter between them; and adjusting means extending between the said members and operable thereon for varying the degree of tension of the said material against one edge of the material supporter.

5. A material holder for sewing machines comprising a grooved member; a wedge adapted to extend within the grooves in the said member; a jaw; and adjusting means operable on the jaw to hold one portion of the material to one surface of the said member and operable to move the wedge against a portion of the material within the said groove to increase the tension on the material and to allow the wedge to move to decrease the tension on the material, said jaw being independent of said wedge.

6. A material holder for sewing purposes comprising a material-supporting plate having two flat surfaces terminating in an edge; means for securing material to the supporting plate; and adjusting means operable on the said securing means for varying the degree of tension of the said material againstthe said edge of the material supporting plate.

7. A material holder for sewing puposes comprising a material supporter having oppositely disposed surfaces terminating in an edge; means for securing a strip of mate-' rial around said edge and across said surfaces; and adjusting means operable on the securing means for varying the degree of tension and pressure of the said material against the said edge of the material supporter.

8. A material holder for sewing purposes comprising a plate adapted to have a strip of flexible material folded around one edge thereof; two material-securing members; and means operable to move one of said members against one portion of the material and operable to move the other member against another portion of the material to increase the tension and pressure of the latter around and against the said edge of the plate, said moving means also being operable to allow said members to move to decrease the tension and pressure of the material around and against the said edge of the plate.

9. The combination of a reciprocable needle; a plate for supporting a piece of strip material, one end of said strip being turned around one edge of the plate, the second end of the strip being pressed against the turned portion of the first-mentioned end; a plurality of clamping jaws; and adjustable means operative on the jaws to clamp and stretch the strip material against the edge of the plate .so as to permit it to be stitched to the other end by the needle.

10. The combination with a sewing machine including a work plate, a needle, presser foot, and feed plate, of a clamp plate for supporting a piece of strip material; means cooperable with the clamp plate to stretch one end of the strip material around a free edge of the clamp plate so as to lap the other end; a slide; a guide carriage movably mounted on the slide and pivotally connected to the clamp plate, said clamp plate actively resting against the feed plate and moved by means of the latter to feed the lapped ends of the strip to the needle to be blind seamed.

11. The combination with a sewing machine including a work plate, needle, presser foot and feed plate, of a clamp plate for supporting a piece of strip material, clamping means cooperable with the clamp plate to stretch one end of the strip material around a free edge of the clamp plate so as to lap the other end, a slide base, a slide on the base, a nut on the slide, an adjustment screw on the base having an extension engaging by the guide carriage, trunnions on the clamp plate adapted to fit in the slots of the bearing plates, said clamp plates actively resting over and moved by the feed plate to feed the lapped ends of the strip to the needle.

12. The combination with a sewing machine including a work plate, needle, presser foot and feed plate, of a clamp plate for supporting a piece of strip material, said clamp plate having a groove formed in one face and a corresponding projection on the opposite face, an upper jaw having a clamp face coincident with the projection on the clamp plate to firmly hold one end of the strip, a wedge cooperative with the groove to firmly hold the other end of the strip material, a slide base, a slide on the base, a nut on the slide, an adjustment screw on the base having a threaded extension engaging the nut, a standard carried by the slide, a guide carriage, roller bearings journaled in the standard and upon which the guide carriage slides, slotted bearing plates carried by the guide carriage, trunnions on the clamp plate adapted to fit in the slots of the bearing plates, said clamp plate actively resting over and moved by the feed plate to feed the lapped ends of the strip to the needle.

18. The combination with a sewing machine including a Work plate, needle, presser foot, and feed plate, of a plate for supporting a piece of strip material, said strip material having its ends lapped and pasted together; means cooperable with the plate for stretching the strip material firmly around and outer end of the strip material to the needle.

In testimony whereof, I have signed my 25 by the feed plate to feed the folded portion I name to this specification, in the presence of 30 two subscribing Witnesses.

WILLIAM MORRISON.

Witnesses AUGUSTUS B. Corrns, J 0s. H. KLEIN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, 2D. 0. 

